Material for attenuating impact energy

ABSTRACT

A new and novel impact energy attenuation material, impact energy attenuation module employing the material and a fit system for optimizing the performance thereof is provided. Non-linear energy attenuating material consisting of a plurality of loose particles is employed for impact energy dissipation. The loose particles are preferably spherical elastomeric balls. An impact energy attenuation module includes a container that holds the loose particles. The impact energy attenuation module can be provided in a wide range of sizes and shapes and the loose particles can be provided in different materials, sizes, density, compaction and hardness to suit with the application at hand. A matrix of impact energy attenuation module are provided about the surface of a shell to provide the required impact energy attenuation. The material, impact energy attenuation module and system of the present invention are well suited for protection of body parts and other cushioning and protection needs.

CROSS REFERENCE TO RELATED APPLICATION

This application is divisional continuation of non-provisional patentapplication Ser. No. 12/946,811, filed on Nov. 15, 2010, which isrelated to and claims priority from earlier filed provisional patentapplication Ser. No. 61/261,544, filed Nov. 16, 2009; provisional patentapplication Ser. No. 61/261,568, filed Nov. 16, 2009, provisional patentapplication Ser. No. 61/261,613, filed Nov. 16, 2009 the entire contentsof each of the foregoing are incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention generally relates to impact energy attenuation,and particularly to padding and cushioning systems intended to reducetrauma resulting from impacts to parts of the body, such as the head.Moreover, the present invention relates the general personal protectionfield, in general, which includes helmets, pads, armor, sports gear,clothing, worker safety equipment, packaging, vehicle interiors,barriers and pads for threat objects, and the like.

The present invention relates to a new and novel way to attenuate impactenergy using loose particles contained in resilient structures whilebeing arranged and customized to optimize such attenuation of energy.

For ease of discussion and illustration, the present invention will beillustrated and discussed in detail in connection with the field ofpersonal protection, namely, helmets. This is just one example of themany applications of the present invention. It should be understood thatthis in no way intended to limit the scope of the present invention.

In the field of personal protection, protective gear for professionaland recreational athletes, sport enthusiasts, military personnel andconstruction workers are well known in the art. There are manyapproaches to reducing impact energies transferred to the user during animpact. As can be well understood, protection of the head is of highconcern due to the risk of head trauma and other serious injuries.Therefore, protection of the head is of critical importance.

In the prior art, helmets are well known to protect a users head fromskull fractures and other such trauma. This was accomplished primarilyby some type of rigid outer shell. Over time, padding was added toreplace webbing based suspension systems. Although padding has improved,these prior art systems still have significant problems and suffer frommany disadvantages. One typical shortcoming of prior art helmetprotection systems is inadequate protection over a range of impactenergies typically encountered in activities they were intended for.Another typical shortcoming of the prior art is their inability tosignificantly reduce rotational (off axis) impact energies. Anothertypical shortcoming of the prior art is their inability to consistentlyfit a large range of users head shapes and sizes. Another typicalshortcoming of the prior art is using impact energy attenuation systemsdesigned for adult helmet systems in children's and youth helmets.

There are many types of helmets provided in the prior art in an attemptto address the foregoing concerns and shortcomings in prior art helmetdesign. Contact sports such as American football, hockey and lacrossehave developed and refined helmet types suited to the play of thosesports while decreasing head injuries. Similarly, climbing helmets, snowsports helmets motor sports helmets and bike helmets have evolved andare widely worn by recreational and professional users. A majority ofthese helmets employ a rigid or semi-rigid shell. It is understood inthe art, that a hard shell protects the skull from fracture anddistributes the impact energy over a larger area. Most bike helmetsutilize expanded polystyrene material for their construction. Thisapproach to the shell/padding allows for a light weight, affordableproduct.

In addition, most helmets have fit systems allowing the user to adjustthe size of the helmet to better fit their head. Fit is known to have alarge impact on the efficacy of any helmet system by maintainingcoverage during a potential impact situation. Rigid shell systems arechallenged to provide an optimal fit given the range of human headshapes and sizes. Many prior art helmets use pads of the same thicknessthroughout and typically result in either loose areas, tight areas orboth when fitted to a users head. Helmets that use foam pad systems, forexample, may have areas that fit tightly and since the foam in thoseareas is overly compressed, impact mitigation is compromised.Conversely, loose areas do not benefit from additional protectionafforded by that dimension. Expanded polystyrene (EPS) bike helmets, forexample, are rigid throughout where the shell and pad system are one andthe same. As a result, they offer little or no ability to establish anoptimal fit.

Still other systems include air bladders, which can be filled to occupyvoids between the users head and the shell. Still other systems usevariable length head bands that can be adjusted to fit the circumferenceof the users head. Variable length head bands leave potentially largevoids between the band and the shell. User applied low durometer foampads are also well know to adjust fit, but do little to attenuate impactenergy.

In addition, most helmets employ a retention system to ensure the helmetstays properly aligned on the users head. These are typically webbingstraps, sometimes including a cup or other interface for the users chin.

As indicated above, all of the forgoing issues also relate to any typeof protective equipment and devices and not limited to those that areintended to protect the body. Therefore, the same issues are of concernoutside of the field of the personal body protection, of which thepresent invention is also related and has applicability.

Referring specifically now to padding, there are many known systems, anumber of which are discussed below. One common approach for padding inthe prior art is the use of foam materials. Foam materials are based ona manufacturing process that creates an open matrix structure from aplastic compound. There are of two primary types, namely, open cell andclosed cell. Open cell materials rely on the structure of the matrix andelastomeric qualities of the plastic material to provide a dampeningeffect to impact energies. Closed cell materials augment the inherentstructure with air contained in the cells thus storing some of theimpact energy by compressing the air. This stored energy in paddingsystems intended for helmets is generally not preferred because it cancause further trauma to the user. One disadvantage to these materials istheir narrow band of responsiveness to the typical range of impactenergies. Another disadvantage to these materials is their inability toprovide an optimal fit for a wide range of user sizes.

In the current art, one approach to padding is rate sensitive materials,which are very well known. These materials use a range of chemicaland/or mechanical means to increase the material's density as the forceof impact increases. Under normal conditions these materials are soft,but stiffen when impacted to distribute and absorb impact energy. Onedisadvantage to these materials is their slow rate of return to normalonce compressed which makes them less suitable to multi-impactapplications.

Another approach to padding is mechanical materials. These materialscombine the inherent energy diffusing qualities of plastic compoundswith unique structures such as tubes, domes, channels, etc. Onedisadvantage to these materials is the narrow band of responsiveness toimpact energies. Another disadvantage to these materials is the highdegree of stored energy they deliver back through the system after aninitial impact.

Another approach to padding is gel materials. These materials generallycombine viscous liquids with solid particles and can range from loose tostiff. Like rate sensitive materials, one disadvantage to thesematerials is their slow rate of return to normal once compressed whichmakes them less suitable to multi-impact applications. Anotherdisadvantage to these materials is their narrow band or responsivenessto the typical range of impact energies.

Another approach to padding is EPS, mentioned above, often found in bikehelmets. These materials are lightweight amalgams of foamed polystyrenebeads, which are typically molded into rigid or semi-rigid structures.Impact energy is diffused when the structure dis-integrates upon impact.One disadvantage to these materials is their reliance ondis-integration, which makes them unsuitable to multi-impactapplications. Another disadvantage to these materials is the difficultyin knowing if they have been compromised or damaged.

Another approach to padding is expanded polypropylene (EPP). Thesematerials are lightweight amalgams of foamed poly propylene beads, whichare typically molded into semi-rigid structures. Impact energy isdiffused similarly to a closed cell foam material. One disadvantage tothese materials is their inherent capacity to store impact energy andreturn it to the user's head as a rebound impact.

Yet another approach to padding is the use of air. Two approaches arecurrently in use in the prior art. First is air contained within aclosed system, either in static bags or coupled bags that allow for theair to be transferred from bag to bag. The other uses an orifice tocontrol the rate air is expelled. One disadvantage to these systems istheir slow rate of return to normal once compressed which makes themless suitable to multi impact applications.

Performance standards have been developed for some helmet types andother body protective equipment. Bicycle helmets, for example, aresubject to US CSPC testing standards. Football helmets are subject toNOCSAE testing standards. Hockey helmets are subject to ASTM testingstandards. These test standards have helped to ensure that theprotective equipment meets minimum requirements for performance underspecified input criteria and testing criteria regardless of brand orcost. While virtually all helmets commercially available pass theirrespective tests, user injuries with different mechanisms of injurypersist across the board. Within the sports category, this may be due inpart to participants' average size and weight increasing coupled with adrive to push themselves harder to be more competitive. Recent newscoverage of the increase in concussive injuries in American football hasraised the question whether current test standards are appropriate forthat particular injury. Medical science is discovering new links betweenbrain injuries and trauma mechanisms that are helping to inform betterprotection, and eventually improved testing standards.

Regardless of application, users are demanding lighter and lower profilehelmets with more and more energy attenuation. Added weight createsfatigue in the user, but is also known to increase inertia to the headin collisions. Helmet wearers generally and young sport enthusiasts inparticular resist high profile solutions for aesthetic reasons.

In view of the foregoing, there is a demand for a new and novel impactenergy attenuation material.

There is a demand for an impact energy attenuation material that is moreresponsive than prior art materials.

There is a further demand for a new and novel system that can provideimpact energy attenuation.

There is a further demand for a system that can provide a custom fit ofsuch a system for optimal performance thereof.

SUMMARY OF THE INVENTION

The present invention preserves the advantages of prior art impactenergy attenuation materials and systems related thereto. In addition,it provides new advantages not found in currently available materialsand systems and overcomes many disadvantages of such currently availablematerials and systems.

The invention is generally directed to the novel and unique impactenergy attenuation material, module therefor including a container andfit system for optimizing the performance thereof.

First, the present invention includes a non-linear energy attenuatingmaterial consisting of a plurality of loose particles. The inventionprovides an interaction between loose particles and the resultant impactenergy dissipation. Like a ball thrown into a bean bag chair the looseparticle material of this invention translates impact energy into heatthrough friction in a highly non-linear distribution. In a preferredembodiment, the loose particles are preferably approximately (0.1-3 mm)diameter spherical elastomeric balls. One benefit of an elastomericmaterial is a high coefficient of friction between the loose particles,which increases the effective energy attenuation. Another benefit of anelastomeric material is under peak load conditions (“bottoming out”),the loose particles themselves will inherently continue to diffuseimpact energy.

Second, the present invention also provides an impact energy attenuationmodule that includes a container for the foregoing material of looseparticles. This module is preferably deformable. The use of the impactenergy attenuation module of the present invention enables a number ofdesirable outcomes to be achieved.

For example, it has been found that, starting from a spherical volume,which is neutral and symmetrical, the energy from an impact could bedirected along an axis by altering the shape of the container. In thepreferred embodiments of the present invention, these energy focusingshapes are preferably triangular or diamond shaped in cross section,however, it should be understood that other shapes can also be used toguide impact energy into a relatively large “pool” of impact energyattenuating material. By enclosing the loose particle material in avolume with such an energy focusing shape, the material's energydissipation qualities are increased. As will described in detail below,a torus shaped configuration is particularly well-suited for the energyattenuation characteristics of the module of the present invention.

In one embodiment of the module, suited for use with a rigid shell orliner in an example of a helmet head protection device, the shape of themodule is a preferably a hollow torus. A cross-section through the torusshows that it is wider at one end than the other or roughly triangular.This module would orient with the wider side facing towards the expectedimpact and the narrow side facing the head. This orientation provides arelatively large “pool” of impact dissipating material to absorb impactenergy proximal to the shell. The small contact surface at the headallows relatively uninhibited flexure of the torus shape, allowing forthe diffusion of rotational or off axis impacts. This small surface isalso useful to create maximum air circulation/ventilation when theapplication is a helmet. It is possible that this torus configurationmay be inverted or altered to better suit the environment and purpose ofthe impact energy dissipation at hand.

As part of the module, the container for the impact energy attenuatingmaterial can be made from any of a range of elastomeric polymers orother materials capable of sustaining multiple high energy impactswithout failure across a range of environmental conditions. This impactenergy attenuation and simultaneous rotational movement of the overallmodule structure gives the present invention a unique functionality todecrease the displacement, velocity and acceleration of the head in bothlinear and off axis impacts.

Further, the container for the material, including loose particles,provides a module that provides a degree of memory, returning the looseparticles to their original or neutral state quickly after an initialimpact thereby enabling the system for further impacts. The pad of thepresent invention can reset itself in a time period of approximately 50milliseconds to approximately 5 seconds. This memory stores very littleinertial energy thereby avoiding any negative effects associated with“spring back” of the module.

The efficacy of the impact dissipation material is partially dependenton the container portion of the module, which holds the material. Boththe shape of the container and the material used for the containeraffect the overall system performance. How tightly the material iscompressed in the container will also affect system performance and canbe tuned to the particular application at hand. As can be understood,higher pressures applied to the loose particle compound by the container(either through overfilling or evacuation of air), slows the movementbetween particles during an impact, effectively hardening the materialto mitigate higher impact forces. Lower pressures result in a softermaterial and mitigate lower impact forces.

Another feature of the present invention is to provide an optimal fit tothe environment at hand. For example, in the example environment of abody protection helmet device, there is a need to custom fit that devicethe individual's head shape and size. The fit of a helmet relative tothe head is understood in the field to reduce the severity of energytranslated through the system, but is difficult to achieve usingconventional means. For example, the range of head shapes and sizes whenconsidering the fit of a helmet cannot be consistently fit using asingle thickness of foam or a single size of pad. To ensure maximumenergy dissipation, each pad installed in the system should preferablybe partially compressed by height when fitted to the users head.

Still further, the present invention provides easily exchangeablemodules to allow the user to replace damaged modules, increase ordecrease the density of any module in the system, and or re-fit thehelmet.

Also, the present invention provides the dissipation of impact energyfrom any angle of incidence. By enclosing the loose particle material ina container with a relatively small attachment member to a rigid shellor liner, the container is free to move or smear in line with the force,and thus not transfer those forces to the users head.

The present invention also provides dissipation of impact energies frommultiple impacts. By enclosing the loose particle material in acontainer made from a resilient material with some degree of memory toform the impact energy attenuation module, the loose particles of thematerial is quickly reset after an initial impact and thus prepared forfurther impacts.

The present invention also dissipates equal impact energy in less volumecompared to prior art materials

Therefore, it is the object of this invention to provide a new and novelimpact energy attenuation material.

An object of the present invention is to provide a material with anincreased range of impact energy attenuation.

It is further the object of this invention to provide a material, moduleand system that can attenuate impact energy regardless of incidenceangle of the impact.

It is further the object of this invention to provide a highlyresponsive system that can quickly reset in anticipation of multipleimpacts.

It is further the object of this invention to provide a method fordistributing impact energy attenuation within body protective equipment.

It is further the object of this invention to provide a method fordistributing impact energy attenuation within a module that is insertedinto body protective equipment.

It is further the object of this invention to provide a method fordistributing impact energy attenuation within a helmet liner or helmetshell.

It is yet a further the object of this invention to ensure an optimalfit of body protective equipment.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features which are characteristic of the present invention areset forth in the appended claims. However, the invention's preferredembodiments, together with further objects and attendant advantages,will be best understood by reference to the following detaileddescription taken in connection with the accompanying drawings in which:

FIG. 1 a is a perspective representational view of the interaction ofthe particles of the present invention;

FIG. 1 b shows example stages of attenuation of impact energy achievedby the particles of FIG. 1 a.

FIGS. 2 a-f illustrate a number of prior art helmet configurations;

FIG. 3 is a top view of the impact energy attenuation module of thepresent invention;

FIG. 4 is a bottom view of the impact energy attenuation module of thepresent invention;

FIG. 5 is a cross-section view through the line 5-5 of FIG. 3;

FIG. 6 is a cross-sectional view of the impact energy attenuation modulebeing installed into a rigid outer shell;

FIG. 7 is a cross-sectional view of the impact energy attenuation moduleinstalled into a rigid outer shell;

FIG. 8 is a cross-sectional view of the impact energy attenuation modulein a neutral loaded condition;

FIG. 9 is a cross-sectional view of the impact energy attenuation modulein an in-use loaded condition.

FIG. 10 is a cross-sectional view of the impact energy attenuationmodule under a peak load condition;

FIG. 11 is a cross-sectional view of the impact energy attenuationmodule in an in-use preloaded condition;

FIG. 12 is a cross-sectional view of the impact energy attenuationmodule under an off-axis impact load condition;

FIG. 13 is an alternative embodiment of the impact energy attenuationmodule and shell with a recess in the inner surface of the shell;

FIG. 14 is the alternative embodiment of FIG. 13 under an impact load;

FIG. 15 is another alternative embodiment of the impact energyattenuation module and shell with a larger recess in the inner surfaceof the shell;

FIG. 16 is the alternative embodiment of FIG. 15 under an impact load;

FIGS. 17 a-h illustrate containers of differing heights and widths thatcan be used in a impact energy attenuation module in accordance with thepresent invention to hold particles of the present invention;

FIGS. 18 a-d illustrate different angles of impact possible to the head;

FIG. 19 is a cross-sectional view of the centered three-piece embodimentof the impact energy attenuation module installed on a rigid shell;

FIG. 20 is a cross-sectional view of the impact energy attenuationmodule of FIG. 19 isolated;

FIG. 21 is an exploded cross-section view of the impact energyattenuation module of FIG. 20;

FIG. 22 is a perspective exploded view of the impact energy attenuationmodule of FIG. 21;

FIGS. 23 a-d is a perspective view of the centered three-piece impactenergy attenuation module in different levels of load;

FIG. 24. Is a cross-sectional view of the off center three pieceembodiment of the impact energy attenuation module installed on a rigidshell;

FIG. 25 a-e show the impact energy attenuation module of FIG. 24;

FIG. 26 is an exploded cross section view of the impact energyattenuation module of FIG. 24;

FIG. 27 a-e is a perspective view of the off center three-piece impactenergy attenuation module in different levels of load;

FIGS. 28 a-d are perspective view of the matrix array of impact energyattenuation modules on an helmet;

FIGS. 29 a-b illustrate a front perspective and side view of a helmetwith centered impact energy attenuation modules installed thereon;

FIGS. 30 a-b illustrate a front perspective and side view of a helmetwith off center impact energy attenuation modules installed thereon;

FIGS. 31 a-c illustrate heads of different sizes;

FIGS. 32 a-c illustrates heads of different shapes;

FIG. 33 a-d illustrates a matrix array of preferred contact points; and

FIG. 34 a-d illustrates the present invention used as both a compressionand tension force dissipator.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning first to FIG. 1, detail of the impact energy attenuationmaterial 10 of the present invention is shown in detail. Preferably,this material, generally referred to as 10, is made up of a number ofdiscrete particles 12. This loose particle material 10 may be solidplastic beads, hollow plastic beads, glass microspheres and ceramicmicrospheres. Depending on the application, larger or smaller particles12 can be used. In a preferred embodiment, the loose particles 12 arepreferably approximately 0.1-3 mm diameter spherical elastomeric balls.A mixture of sizes, shapes, and materials for the loose particles 12 isalso possible. Further embodiments may include non-spherical particles12 ranging from oval rounds to hard edged multi-hedron shapes(tetrahedrons, cubes, etc.). In the preferred embodiment, the durometerof the elastomeric particles 12 are preferably in the range ofapproximately Shore A 10 to approximately Shore A 100.

The characteristics and performance of the impact energy attenuationmaterial 10 is best described in connection with its use in an actualapplication. For example, the material 10 may be used for a number ofapplications, such as body protection, in the form of a helmet toreplace the conventional prior art constructions seen in FIGS. 2 a-f.FIGS. 2 a-b show a prior art strap suspension configuration 14 withstraps 16 and shell 18 to rest on the head 20 while FIGS. 2 c-d shows aunitary layer of foam padding configuration 22 with foam padding 24between the shell 18 and the head 20. Additional fixed layers 26 arealso commonly provided. FIGS. 2 e-f further shows another embodiment 28with intermittent swatches of padding 30 between the user's head 20 theouter shell 32. These prior art configurations provide inferior impactenergy attenuation.

Referring back to the present invention, as in FIGS. 6 and 7, the systemincludes a rigid outer shell 34 with an impact energy attenuation module36 removably attached thereto. The module 36 includes impact dissipationmaterial 10 with particles 12 that may be encapsulated in a multiplicityof containers 37 installed to hold the object to be protected insuspension. The containers 37 are preferably in the form of a sealedbladder. Further details of the interconnection of the container 37 tothe rigid outer shell 34 is shown in FIGS. 3-9. More specifically, FIG.3 shows a top view of the container 36 while FIG. 4 shows a bottom viewthereof. FIG. 5 is a cross-sectional view through the line 5-5 of FIG. 3to illustrate the impact energy attenuation module 36 with a container37 of a torus shape with material 10, including the loose particles 12,residing therein.

As can be seen in FIGS. 6 and 7, the impact energy attenuation module 36of the present invention is removably affixed to the rigid outer shell34. For example, a post 38 and button 40 is preferably provided toengage with an aperture 42 in the rigid outer shell 34. As in FIG. 7, itcan be seen that the button 40 passes through the aperture 40 to securethe impact energy attenuation module 36 in place. A seat 42 may also beprovided on the opposing side of the rigid outer shell 34 so that thebutton 40 of the impact energy attenuation module 36 lies flush with theouter surface 34 a of the rigid outer shell 34. As will be described indetail below, to achieve the proper fit of irregular objects within arigid shell 34, impact energy attenuation modules 36 of variousdimension and density can be interchangeably attached to the interior ofthe shell 34.

Turning now to FIGS. 8 and 9, it can be seen that positive pressure canbe achieved by loading or partially compressing each impact energyattenuation module 36 with the object to be protected, such as a head20, in this example. More specifically, FIG. 8 illustrates the mountedimpact energy attenuation module 36 in a neutral or unloaded condition.The torus-shaped impact energy attenuation module 36, filled with theimpact energy attenuating material of loose particles 12 in a container37, remains in a fully formed shape. This is in contrast to FIG. 9 whichshows loading of the impact energy attenuation module 36, namely bycommunication of a bottom impact surface 20 (e.g. a person's head) andthe rigid outer shell 34. The impact energy attenuation module 36,deforms when presented with this impact surface.

It should be noted that when used without a rigid outer shell 34, theimpact dissipation material 10 with particles 12 may be encapsulated bya container 37 or containers 37 and held against the object to beprotected or the threat object, such as a ski lift pole, steering wheel,and the like, by any number of conventional means, including fasteners,straps, hook and loop material, or integrated into an article ofclothing or equipment, and the like. As when used with a shell 34, anequal positive pressure on the object to be protected should beachieved, although this is not required.

The inertial energy associated with a linear impact compresses thematerial 10 of particles 12, as can be seen by the arrows in FIG. 9.This initial phase of an impact, is, for example, typically 2-200 msecbut could also be longer or shorter depending on the application. Inaccordance with the present invention, the inefficiency of thespherical, high friction material 10 translates a portion of the impactenergy into heat. Referring back to FIG. 1, such translation of heat canbe seen by the interaction of particles 12 relative to each other. Thenext phase of a typical impact surrounds the event of “peak load”.During a peak load that exceeds the material's ability to translate thatenergy into heat through friction, the force “bottoms out” against abroader but thinner area of the loose particles 12. With this invention,a further degree of energy dissipation is provided by the elastomericnature of the loose particles 12—through friction within the elastomericmaterial. The next phase of a typical impact is the translation of theremaining energy through to the object 20 to be protected. The finalphase in the cycle of a typical impact is the duration to “reset” thematerial 10 for subsequent impacts. This reset typically occurs in therange of 50 milliseconds to approximately 5 seconds but this reset timecould be shorter or longer. This process to bring the loose particles 12back into a neutral state is accomplished by the material 10 and in this“rebound”, the nature of the material 10 of loose particles 12 mitigatesthe negative affects associated with stored energy or spring back.

FIG. 10 illustrates an impact that is primarily linear, or “on axis” tothe object to be protected. In this case, the impact dissipationmaterial 10 reduces the likelihood of damage in at least two ways. Firstby translating a portion of the impact energy into heat and secondly bydiffusing the energy across an area larger than the initial impact. Inthis case and during a “peak load” phase, the nature of the looseparticle material 10, with its loose particles 12, will create an evenload across the surface of the container 37 of the impact energyattenuation module 36.

In contrast, during impacts that are primarily rotational, shear or “offaxis” to the object to be protected, the impact dissipation material 10reduces the likelihood of damage by freely shifting under the force,thus preventing that energy from entering the system. Such a conditioncan be seen in FIGS. 11 and 12. FIG. 11 illustrates pre-loading of theimpact energy attenuation module 36 between the impact surface and therigid shell 34. FIG. 12 shows the impact energy attenuation module 36under an off-axis load resulting from an off-axis impact to the outerrigid shell 34. In this case, the impact energy attenuation module 36conforms to improve impact energy attenuation.

Another example of a rigid shell and pad configuration is shown in FIGS.13 and 14. In this embodiment, the rigid outer shell 44 includes atorus-shaped seat 44 a to received the torus-shaped impact energyattenuation module 36. FIG. 13 shows this configuration at rest whileFIG. 14 shows this configuration under impact load. In this case, as inFIG. 14, the impact energy attenuation module 36, namely the containerportion 37, flexes outwardly to provide a particular profile that issuitable for certain environments.

FIGS. 15 and 16 show yet another embodiment where the receiving seat 46a on the inner surface of the rigid shell 46 is larger than the width ofthe impact energy attenuation module 36 when at rest in the neutralposition. As in FIG. 16, when the impact energy attenuation module 36 isunder load, it remains contained within the boundaries of the receivingseat 46 a. As above, this particular configuration may be more suitablefor certain environments. These configurations can permit the impactenergy attenuation module 36 to bottom out yet still maintain arelatively low profile of the overall shell 46.

Therefore, the impact energy attenuation modules 36 of different sizesand configurations of the present invention can be customized to achievethe proper fit of irregular objects within a rigid shell. As seen inFIGS. 6 and 7, discussed above, impact energy attenuation modules 36 ofvarious dimension and density, with respective containers 37, can beremovably attached to the interior of a shell to provide a custom fitand configuration for the user.

When used without a rigid outer shell 34, the impact dissipationmaterial 10 may be encapsulated by a container 37 or containers 37 andheld against the object to be protected or the threat object by anynumber of conventional means (fasteners, straps, hook and loop material,or integrated into an article of clothing or equipment, etc.) As whenused with a shell 34, an equal positive pressure on the object to beprotected should be achieved.

The size, shapes and configurations of the impact energy attenuationmodules 36 and their respective containers 37 can be modified in any wayto suit the application at hand. While a torus shape is preferred, anyshape may be used and still be within the scope of the presentinvention. Also, a range of sizes of containers 37, such as varying inheight and width, can be employed, as seen in FIGS. 17 a-h. For ease ofillustration, the impact energy attenuation material 10 is not shown inthese figures.

Turning now to FIGS. 18 a-d, different angles of impact are shown toillustrate how the material 10 and impact energy attenuation module 36can accommodate such angles of impact forces 48. FIGS. 18 a and 18 billustrate an “on axis” or “linear” impact trajectory 48. During theseon axis impacts 48 that are primarily linear, the impact energyattenuation module 36 reduces the likelihood of damage in at least twoways. First by bounding and guiding the loose particles 12 to translatea portion of the impact energy into heat and secondly by the nature ofits triangular shape, diffusing the energy across an area larger thanthe initial impact. This load spreading can be best seen in FIG. 10.Also, during a “peak load” phase, the nature of the material 10 willfurther dissipate impact energy.

FIGS. 18 c and 18 d illustrate an “off axis” or “rotational” impacttrajectory 50. During these impacts that are primarily rotational, shearor off axis to the object to be protected, the impact energy attenuationmodule 36 reduces the likelihood of damage by freely deforming under theforce, preventing a portion of that energy from entering the system.This load spreading from a rotation impact trajectory can be seen inFIG. 12.

When implemented within a helmet, the nature of head shapes and sizesrequires that the helmet be fitted to achieve maximum performance. Inone embodiment, a fitter trained in the fitting process undertakes thecustomization of the shell to fit its user. A wide range of shellsappropriate to many activities, such as cycling, contact sports,construction, and the like, will be available in sizes to fit mostuser's heads. A fitter trained in the fitting process will not onlyensure compliance with safety standards, but adds value in the way ofservice. This process may occur in a specialty retail shop or in aninstitution where the staff can be trained. The fitting process mayutilize a device that quickly determines the optimal location and padsizes for a particular user's head. The fitter then installs the correctpads in the chosen shell and confirms the fit on the users head.

In another embodiment, a range of the sizes of the impact energyattenuation module 36 may be included with the shell 34 withinstructions for the user to fit the helmet without assistance.

For applications where the space between the shell 34 and the object tobe protected 20 is more consistent, a pre-determined set of impactenergy attenuation modules 36 are preferably installed by an appropriatemethod.

For applications where no shell 34 will be used, impact energyattenuation modules 36 are preferably selected based on the likelyimpact forces to be encountered.

The impact energy attenuation module 36 may also be modified, inaccordance with the present invention to include a three-piececonfiguration 52 for even further improved impact energy attenuation.Referring to FIGS. 19-23, a centered version includes a cross-sectionalview of the three-piece configuration 52 is shown to include a centralelongated spherical container 54 that serves as an impact energyfocusing structure, which contains the material 10 of loose particles12, as described above. The spherical container 54 is preferablypermanently attached to a base member 56. The base 56 in thisthree-piece embodiment 52 creates a mechanical connection with the rigidshell 34 by engaging through an aperture 58 therein. It also serves toprovide a degree of impact energy attenuation by means of the reversecamber surface 60 to which the energy attenuating components areattached. Furthermore, upon a high energy impact, the base 56 acts tohold the parts together which might otherwise fracture and disperse.FIGS. 23 a-d illustrates, in steps, how the centered three-piececonfiguration 52 attenuates impact energy ranging from no load in FIG.23 a to an initial load in FIG. 23 b to a partial load in FIG. 23 c to afully loaded pad in FIG. 23 d. The compression and movement of sphericalcontainer 54 and intermediate member 62 can be seen.

Residing between the base member 56 and the spherical container 54 is apreferably torus-shaped element 62, which preferably is of a moldedfoam, such as EPS, EPP or any of the many foam materials known in theart. The torus-shaped element 62 is also preferably permanently attachedto the base 56, such as by gluing, overmolding or any other method ofaffixation. This inner surface 62 a of the torus-shaped element 62 facestoward and is adjacent to the spherical container 54 with looseparticles 12 therein. Its shape is configured to enhance the energyfocusing aspect of the spherical container 54 with loose particles 12,further directing impact energy.

A non-centered or offset version 64 of the three-piece impact energyattenuation module is shown in FIGS. 24-27. The functionality of thisoffset impact energy attenuation module 64 provides functionally that isidentical to the “centered” version 52 of the impact energy attenuationmodule of FIGS. 19-23 with the exception of fit. A spherical container66 intermediate member 68 and base 70 are provided in similar fashion tothe centered version 52. This offset configuration 64 allows a user tofine tune the fit of each impact energy attenuation module 64 in ahelmet (represented by a shell 34) by rotating it circularly within themechanical connection to the shell or liner 34. FIGS. 25 a-e show thenon-centered or offset version 64 and how it can be rotated for customfit to position the spherical container 66 where desired.

Depending on the distribution of the matrix within the shell or liner34, any impact energy attenuation module 64 may align with a high pointon the users head 20 (not shown in FIG. 24). If by turning the impactenergy attenuation module 64, it may instead align with a lower point,the resulting increase in space may allow for a thicker and thereforehigher energy attenuating impact energy attenuation module 64 to beinstalled. FIGS. 24 and 25 a show the offset three-piece pad container64 at rest. FIGS. 27 a-e illustrates, in steps, how the offsetnon-centered three-piece configuration 64 attenuates impact energyranging from no load in FIG. 27 a to a fully loaded impact energyattenuation module 64 in FIG. 27 d. FIG. 27 e shows a deflected impactenergy attenuation module 64 after bottoming out in FIG. 27 d.

In this preferred embodiment, when installed in a rigid helmet shell orliner (see helmet assembly of FIGS. 6 and 7 for example) a plurality ofimpact energy attenuation modules 36, 52 and/or 64 preferably form apassive matrix 72, as illustrated in FIGS. 28 a-d. As in FIGS. 28 c-d,the rigid shell 34 distributes some of the total impact energy to eachof the impact energy attenuation modules surrounding the locus ofimpact. The appropriate centered and/or non-centered pads 36, 52 and/or64 are selectively used for a custom fit. For example, FIGS. 29 a-billustrate the mounting of a centered three-piece pad impact energyattenuation module 52 installed within a desired matrix 72 of padaffixed to the rigid shell 34. Similarly, FIGS. 30 a-b illustrate themounting of a non-centered/offset three-piece impact energy attenuationmodule 64 installed within a desired matrix 72 of impact energyattenuation modules 64 affixed to the rigid shell 34.

In lower energy impacts, the loose particle container 54, 66 is engagedthen immediately returns to its original shape and position. In higherenergy impacts, the loose particle container 54, 66 is initially engagedthrough its peak capacity. Upon bottoming out, the impact energy thenengages the torus shaped foam module 62, 68, which in this preferredembodiment has a higher threshold of energy attenuation. With sufficientimpact energy, the inherent attenuation qualities of the loose particles12 of the material 10 as well as the reverse camber of the base module56, 70 are engaged as well.

Another important aspect of the present invention is the ability to finetune the performance characteristics and fit of an impact system. Inthat connection, the invention enables individual impact energyattenuation modules in an impact system to be adjusted to align with theanatomy of the user. Thus, the invention enables any single impactenergy attenuation module in the system to dissipate impact energy bothin tension and compression.

When implemented in a helmet, such as in the form of a shell 34 as inFIGS. 6 and 7, the nature of head shapes and sizes requires that thehelmet, i.e. the shell 34, be fitted to achieve maximum performance. Awide range of shells 34 appropriate to many activities, such as cycling,contact sports, construction, and the like, are available in sizes tofit most user's heads 20.

First, a rigid shell type is selected based on the intended use—forexample, bicycle, football, baseball, hockey, and the like, then aparticular style within that type and finally a size suited to the usershead size, as see in FIGS. 31 a-c, and shape, as seen in FIGS. 32 a-c.Because the range of actual head shapes 20 a-c and sizes variesconsiderably from the head form used to manufacture a shell 34, therewill be some void between the users head 20 a-c and the inner surface ofthe shell 34, and that void will be inconsistent. While severalsolutions have been identified to address this issue, as in prior artFIGS. 2 a-f, none except a custom fitted product reduce the void spaceswith impact dissipating material 10. To address this need, the presentinvention provides a shell 34 with a plurality of connection points onthe interior surface, which may include mechanical fasteners, hook andloop, adhesive or the button aperture interconnection, shown in FIGS. 6and 7.

Once a shell 34 is selected, impact energy attenuation modules 36, 52and/or 64, as seen in FIGS. 3-5 and FIGS. 20 and 24, of a particularthickness, are selected from an array of different sizes and shapes, asin FIG. 17, to ensure a proper fit to the users head. Each impact energyattenuation module, when installed in the system is preferablycompressed 10-25% by height when fitted to the users head 20 to ensuremaximum energy dissipation efficiency, as illustrated in FIGS. 8 and 9.Such compression is just an example of the extent of compression forthis particular example. Different particles 12 with different impactenergy attenuation module structures in different environments mayachieve compression that is more or less than the compression indicatedabove.

To further ensure the system is suited to the intended use, impactenergy attenuation modules of a particular density and surface area areselected based on risk factors such as weight of user, likelyvelocities, and types of impacts. Larger area and higher density impactenergy attenuation modules are selected for heavier users with higherrisk factors and smaller, lower density impact energy attenuationmodules are selected to lighter users with lower risk factors.

A final aspect of fit involves aligning impact energy attenuationmodules with specific anatomic structures of the users skull 20 todirect the flow of impact energy into inherently stronger and lessvulnerable areas of the users body. As in FIGS. 33 a-d, preferably ninepoints, in a matrix 72, on the skull 20 have been identified asindividually optimal for strength as well as for creation of a matrix 72with a high ratio of energy dissipation to physical structure. Ofcourse, more or less than nine points may be employed and still bewithin the scope of the present invention.

To adjust the fit of a helmet, namely a shell 34, to the users head 20,the fitter further refines the impact energy attenuation moduleselection to ensure that each impact energy attenuation module in thesystem is evenly loaded or partially compressed against the users head20 once installed in the shell 34. The space between the users head 20and the inside of the shell 34 is used to determine each impact energyattenuation module's thickness. The effect of this fitting will ensure acomfortable, safe helmet.

The fitting process may utilize a specialized device that quicklydetermines the optimal location and impact energy attenuation modulesizes for a particular user's head 20. The fitting process may utilize aspecialized computer program to compile the collected data from the userto suggest specific impact energy attenuation modules for optimal fit.

Once the impact energy attenuation modules are selected, the impactenergy attenuation modules are inserted into the chosen shell 34 toalign with the users cranial structure. Any impact energy transmittedthrough the system to the users heads 20 should follow a path thatreduces the potential for injury.

When used without a rigid outer shell 34, the impact energy attenuationmodules will be held against the object to be protected or the threatobject by any number of conventional means, such as by fasteners,straps, hook and loop material, or integrated into an article ofclothing or equipment, and the like.

The embodiment of FIG. 34 a-d illustrates an embodiment used as both acompression and tension force dissipater 100. To take full advantage ofthe inherent impact mitigation qualities of certain impact energyattenuation modules 102, similar to modules 36, 52 and/or 56, a harness104 may or may not be added to a system that includes a rigid shell, asin FIGS. 34 c and 34 d. FIGS. 34 a-b show this embodiment without aharness 104 while FIGS. 34 c-d shows use of a harness 104. The harness104 is intended to snugly fit the object to be protected 106. In thisuse, each impact energy attenuation module 102 in the system is attachedboth to the inside of the rigid shell 108, and the harness 104. Upondelivery of an impact, the harness 104, links the impact energyattenuation modules 102 actively so the compressive force on anyparticular impact energy attenuation module 102 is slowed by the tensileforce on the opposite impact energy attenuation module 12. This conceptcan be applied to both single axis and multi axis applications.

It would be appreciated by those skilled in the art that various changesand modifications can be made to the illustrated embodiments withoutdeparting from the spirit of the present invention. All suchmodifications and changes are intended to be covered by the appendedclaims.

What is claimed is:
 1. A material for attenuating the impact energy froman incoming impact force, sufficient enough to cause trauma to a bodypart, to prevent trauma to a body part, comprising: a plurality ofparticles configured and arranged within a volume of space; at least oneof the plurality of particles capable of being in communication with anincoming impact force having an impact duration within a time range ofapproximately 2 milliseconds to approximately 5 seconds; whereby uponcommunication of the at least one of the plurality of particles withother ones of the plurality of particles within the volume of space dueto an incoming impact force, the incoming impact force is attenuated viathe other ones of the plurality of particles within the volume of space.2. The material of claim 1, wherein the particles are spheroid.
 3. Thematerial of claim 1, wherein the particles are non-spheroid.
 4. Thematerial of claim 1, wherein the particles are made of a materialselected from the group consisting of: plastic, glass and ceramic. 5.The material of claim 1, wherein the particles are solid.
 6. Thematerial of claim 1, wherein the particles are hollow.
 7. The materialof claim 1, wherein the particles have a diameter in the range ofapproximately 0.1 mm to approximately 3.0 mm.
 8. The material of claim1, wherein friction between the plurality of particles increase theefficacy of the non-linear energy attenuation.
 9. The material of claim1, wherein the plurality of particles have a durometer in the range ofapproximately Shore A 10 to approximately Shore A
 100. 10. The materialof claim 1, wherein the material resets to its original unloaded restingposition and shape after an impact thereto within a time range ofapproximately 50 milliseconds to approximately 5 seconds in preparationfor subsequent impact to avoid impact due to a subsequent incomingimpact force to the body having a duration within the time range of 2milliseconds to 5 seconds.